Heating element for drying apparatus



March 23, '1937. A. BERGMANN HEATING ELEMENT FOR DRYING APPARATUS Filed Dec. 13, 1934 Pfg.

// J/ /N VENTOR o or o o o a w o ,o o o o o oo o Q O o o o oo o o o o c w c w w o o o o o o o o o o oo mu o o o o o 00A o9 0% o o oo n o .10o n/ lo o O o 0A o o o o o o o e /o o o oA. o ooo O 0 o /o oo /o oo w om 0 00 Q O 0 0 0 QA Y B Patented Mar. 23, 1937 UNTTED STATES RATUS HEATING ELEMENT FOR DRYING APPA- Auguste Bergmann, Reims, France Application December 13, 1934,`Serial No. 757,258 In France December 14, 1933 4 Claims.

The invention herein described relates to drying chambers in which textile fibres, threads in layers or in hanks, fabrics, paper and like material are dried by means of the circulation of r hot air.

" In particular, it relates to drying chambers in which the materials to be dried travel over a continuous zig-zag path, between partitions, or plates 4arranged as baffle-plates, each such baiie-plate lo `occupyingalmost the whole length of the chambers and extending in a transverse direction over the entire width of` the Said chambers, from one lateral wall to the other, theheating elements, such as in general tubes heated by the circula- ]Y, tion of steam, being arranged above and below 'i the saidv baffle-plates, and the air thus heated circulating between the balile-plates, its direction of iiow being `either thesame as that of the materials to be dried or opposite to this.

The object .of the invention is to improve the Q efficiency oi the above-mentioned system of heating by means of heating baule-plates, with a View to supplying the necessary heat at each point of the path of `the material to be dried which will u compensate for the heat absorbed by the evapora- 2U tion, the amount of heat depending on the degree of humidity of the material and the degree of saturation of the surrounding air at each point in question, and the improvement being effected n owing to the fact that the heating surfaces `are "0 indirect contact with the air circulating between the balde-plates. The invention also has as another object an improved construction, making it more practical and easier to install, more economical to construct and adaptable to the above- 3*) mentioned classes of drying chambers.

With these objects in view, the invention consists of the provision of heating units or elements that may be arranged to provide a drying chamber having a Zig-zag course for the material to be dried.

Heating elements or units embodying the invention are disclosed in the accompanying drawing in which:

Fig. 1 is a longitudinal, sectional elevation illustrating the type of drying chamber to which the heating units of this invention are especially applicable;

Fig. 2 is a longitudinal, sectional elevation of 50 three of the units embodying the invention, the

two end units being broken away and a section being taken along the line II--II of Fig. 3;

Fig. 3 is a transverse, sectional elevation of the heating unit illustrated in Fig. 2, the section being 55 taken along the line III-III of Fig. 2; and

Fig. 4 is a transverse, sectional `elevation of .a modified form of heating unit, the transverse, sectional elevation being the same as that of Fig. 2.

The drying chamber illustrated in Fig. 1 consists or a metal cabinet having side walls I. Within .the cabinet, adjacent one end, there is a guide roller 2 and at the iront of the cabinet there are guide rollers 3 andll. The material Y{.i to be .dried passes over the guide roller 3 and enters an opening through the frontL wall of the chamber, passes through the chamber to the guide roller .2 and back to the front of the chamber and over the guide roller 4. Two passages at ,diierent elevations through which the material 5 passes are formed'by a series of heatingunits.

Heating units which when arranged in several series iorm a drying chamber similar to that disclosed in Fig. 1, are illustrated in Figs. 2 and 3. The units illustrated in Figs. 2 and 3 include .a Agroup of metal tubesv 9, the length of which is greater .than the width of the drying chamber in which the heating elements are mounted. The `diameters of these tubes may be equal or the several tubes may vary in diameter. A series' `oi rectangular plates ID and two end plates I0', preferably made of aluminum, are mounted on these tubes. The plates I0, I0 and the walls .I have cut therethrough holes to receive the tubes 9. The holes in the plates and the tubes may be .arranged in undulating lines such as indicated inFig. 2 or otherwise as desired. The plates are spaced apart and the edges thereof may be stamped so as to follow the undulating lines of the rows of tubes on which they are mounted. Metal strips II maintain the plates in spaced relation. 'Ihese metal strips II are mounted between successive plates and rest upon the tubes 9. The strips II follow the undulating lines of the rows of tubes.

The strips I I are secured to the plates I0 by solder I2. In addition to this soldering, each element can be, if required, dipped into a soldering bath after it has been constructed, so as to iill up and seal all the interstices which may exist between the tubes and the plates Ill. Any mechanical means may also be utilized for the same purpose during the construction of each element, in order to fasten the plates of metal I0 on the pipes 9: for example, expanding mandrels may be passed into the interior of the pipes, in order to expand the pipes in the plates I0.

In order to facilitate and at the same time to reinforce the assembly of the elements to form a heating baille-plate, the lateral edges of the plates IU may be provided with steps I3 or recesses or projections so as to permit the tting edge to edge of the said plates.

Moreover, the central part of the plates I0 may be provided, between the rows of tubes 9, with one or several apertures I4, in order to permit communication between the spaces separated by the plates, and at the same time to lighten the weight. The two end plates ID', however, are not provided with such apertures, in order that the element may form hollow airtight baiiie plates constituting a heating chest, having surfaces with circumvolutions to improve the mixing of the air.

For the construction and the assembly of the heating baffle-plates in a drying chamber, the elements formed as above described .are arranged for each baille-plate one after the other, and these are assembled in the same plane, between the lateral walls I of the chamber, the ends of the tubes 9 passing beyond the end plates Ill' of an element and being supported on the lateral walls of the chamber, through which they pass by means of holes provided there and arranged in the same way as in the plates I0, all the ends of lthe tubes 9 being connected on an outer wall of the chamber by collecting pipes (not shown) which feed the steam to the chamber, whilst all the opposite ends of these tubes are connected by outlet collector pipes, the heating elements thus assembled form baffle-plates extending alternately from the front wall I of the chamber to a certain distance from the rear wall I, and viceversa. These units are so arranged that a series of units form one longitudinal baille in the drying chamber and another series of units mounted above form with the lower series of units a trans- 'verse passage through which the material to be dried passes.

In a variation of the invention shown in Figure 4, the construction of an element remains approximately similar, with the difference that the group of tubes 9 is eliminated and the chest formed by the assembly of the plates IU and the intervening strips II receives the steam direct, which thus lls all the hollow partition or plate forming a baille, the admission and discharge of the steam being ensured by external lateral pipes in a suitable number, which pass through the walls of the chamber and end in the elements forming each heating baille-plate, which elements may also be made by drawing or casting.

It is well understood that, without departing from the spirit of the invention, modifications, improvements and additions may be made, and also the employment of equivalent means adopted.

I claim:

1. A heating unit for drying chambers of the type described comprising a plurality of metal plates spaced apart and .arranged in parallel relation, each plate having a row of openings extending therethrough, longitudinally of the plate on each side of the longitudinal axis of the plates, the corresponding holes in the several plates being alined, a series of tubes, one extending through each of the alined holes of the several plates, the tubes extending transversely of the heater unit and being of a length greater than the Width of the unit, and a strip of metal in each of the spaces between the plates contacting with the tubes and joined to the plates.

2. A heating unit for drying chambers of the type described comprising a plurality of metal plates spaced apart and arranged in parallel relation, and a pair of strips of metal in each of the spaces between the plates and closing the spaces between the plates to form chambers, the strips of metal being undulating and the corresponding strips between the several plates being alined.

3. A heating unit for drying chambers of the type described comprising a plurality of metal plates spaced apart and arranged in parallel relation, each plate having an undulating row of openings therethrough, extending longitudinally of the plate on each side of the longitudinal axis of the plate, the corresponding openings in the several plates being alined, a series of tubes extending transversely of the plates, one extending through each of the alined openings of the several plates and being of a length greater than the width of the unit, and a pair of strips of metal in each of the spaces between the plates closing the spaces between the plates, each strip of a pair contacting with each of the tubes of one row of the tubes extending through the plates.

4. A heating unit as described in claim 1, the plates of which have stepped edges for joining several heating units together to form a baiiie.

AUGUSTE BERGMANN. 

